The invention relates to a power contact device of an electric control apparatus comprising:                at least a first stationary contact element and a second movable contact element designed to occupy a closed position in which they are in electric contact for establishment and flow of the current, and an open position in which the two contact elements are separated from one another interrupting flow of the current,        and electrodynamic compensation means for keeping the contact elements in the closed position when a short-circuit current occurs, said compensation being performed by means of the electrodynamic attraction effect due to flow of the current taking place in the same direction in the two contact elements.        
The electric control apparatus does not have any breaking capacity but its contacts must imperatively remain closed in the presence of a short-circuit, which is eliminated by a protective circuit breaker connected line-side.